x/(x2+2)+(x2+20/x=-10/3,求X的值

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x/(x2+2)+(x2+20/x=-10/3,求X的值x/(x2+2)+(x2+20/x=-10/3,求X的值x/(x2+2)+(x2+20/x=-10/3,求X的值令a=x/(x²+2)

x/(x2+2)+(x2+20/x=-10/3,求X的值
x/(x2+2)+(x2+20/x=-10/3,求X的值

x/(x2+2)+(x2+20/x=-10/3,求X的值
令a=x/(x²+2)
则(x²+2)/x=1/a
a+1/a=-10/3
3a²+10a+3=0
(3a+1)(a+3)=0
a=-1/3,a=-3
x/(x²+2)=-1/3
x²+2=-3x
x²+3x+2=0
(x+1)(x+2)=0
x=-1,x=-2
x/(x²+2)=-3
3x²+6=-x
3x²+x+6=0
无解
所以x=-1,x=-2

上边的式子貌似打错了?+20应该是+2)吧
如果是这样的话,令X/(X²+2)=t
则t+1/t=-10/3
即3t²+10t+3=0
得t=-1/3或-3
因X的绝对值必小于X²+2
故t的绝对值小于1
故舍去t=1
即t=-1/3
即X/(X²+2)=-1/3即X²+3X+2=0
得X=-1或X=-2